Manual bed leveling starts with raising the bed toward the nozzle

To raise a heated bed manually on a 3D printer, you turn the leveling knobs (usually four brass or plastic screws) underneath the bed platform counterclockwise. Each turn lifts that corner of the bed slightly. The goal is to close the gap between the nozzle and the bed surface until a piece of standard printer paper slides between them with light resistance — this is called the "paper test" and gives you the starting point for a level bed.

The process takes 10 to 20 minutes the first time, depending on how far down the bed has settled. You will need the printer powered on (so the nozzle is at its home position), a sheet of regular 20-pound printer paper, and patience — small adjustments matter more than speed.

Key Takeaways

  • Raise the bed by turning the leveling knobs counterclockwise, one quarter-turn at a time, checking your progress with printer paper after every adjustment.
  • The paper should slide under the nozzle with slight resistance — not tight enough to tear, not loose enough to move freely.
  • Raise all four corners before printing, starting with the corner farthest from you and working toward the nearest, to avoid re-leveling the same spot twice.
  • If the bed is too high (nozzle too far away), the filament will not stick; if too low, the nozzle will scrape the bed or jam plastic into the surface.
  • Check your bed level before every print for the first month, then every few prints once you understand how your printer settles.

Locate the leveling knobs and home the printer

The leveling knobs sit underneath the heated bed platform, one at each corner. On most printers they are brass or plastic screws that thread into the bed support frame. Before you touch them, power on the printer and send it to home position — this moves the nozzle to its starting point, usually the front-left corner of the bed.

Use your printer's menu (usually under "Prepare" or "Home") or send the command G28 if you have a computer connected. Do not manually move the nozzle by hand — the stepper motors need to know where zero is, or your measurements will be wrong. Wait for the nozzle to stop moving before you start adjusting.

Perform the paper test at each corner

Slide a sheet of printer paper under the nozzle. You should feel light resistance — the nozzle should grip the paper slightly but not so hard that you cannot pull it out. If the paper moves freely with no drag, the bed is too low and needs to be raised. If the paper tears or you cannot slide it at all, the bed is too high.

Start at the corner farthest from you (usually the back-right). Turn the knob counterclockwise one quarter-turn, then test the paper again. Repeat until you feel the right amount of resistance. Move to the next corner (back-left), then front-left, then front-right. This order prevents you from re-adjusting a corner you already leveled.

The resistance should feel the same at all four corners. If one corner is much tighter than the others after you finish, go back and adjust it again — the bed may have shifted slightly as you worked.

Avoid common mistakes during manual leveling

The most common error is turning the knobs too far at once. A full rotation raises the bed about 2 to 3 millimeters — far more than you need. Stick to quarter-turns and test after each one. If you overshoot and the bed gets too high, turn the knob clockwise to lower it back down, then approach the correct height from below.

Another mistake is leveling with the printer cold. The bed and nozzle expand slightly when heated, which changes the gap. If your printer has a preheat function, run it before you level. Some printers have a "bed leveling" mode that heats the bed and nozzle to printing temperature automatically — use that if available.

Do not assume the bed is level just because one corner feels right. All four corners must pass the paper test. A bed that is level at one corner but high at another will cause the nozzle to crash into the bed on one side or fail to stick on the other.

Check your work with a test print

After you finish leveling all four corners, run a bed leveling test print — a straightforward square or grid that prints a thin layer across the entire bed. Watch the first layer as it prints. The filament should stick evenly and look like a thin, continuous line with no gaps or ridges.

If the filament bunches up or the nozzle scrapes the bed on one side, that corner is too low. If filament does not stick or looks thin and stringy on one side, that corner is too high. Make small adjustments (one eighth-turn at a time) to the problem corner and print again. This real-world test often reveals leveling issues that the paper test alone does not catch.

Maintain your bed level over time

A heated bed will settle slightly after each print, especially in the first few weeks. Check your level before every print for the first month. After that, check every few prints or whenever you notice the first layer not sticking evenly.

If you find yourself re-leveling the same corner repeatedly, the bed frame or nozzle may be warping from heat. This is normal wear, but if one corner consistently drifts low, you may need to replace the bed springs or check that the nozzle is not bent. For now, re-level as needed — it takes only a few minutes once you know the process.

Frequently Asked Questions

How tight should the paper feel under the nozzle?

The paper should have light resistance — you can pull it out, but the nozzle grips it slightly. If you can slide it freely with no drag, the bed is too low. If the paper tears or you cannot move it at all, the bed is too high. Think of it as the resistance you feel when sliding a piece of paper between two books that are almost closed.

What if one corner keeps drifting low after I level it?

The bed frame or support may be warping from heat, or the spring under that corner may be weakening. Re-level that corner before each print for now. If it happens on the same corner every time, check that the bed is sitting flat on all four springs and that no debris is trapped underneath. Some printers have stiffer springs available as replacements.

Can I level the bed while it is cold?

You can, but the gap will change when the bed heats up. For the most accurate leveling, preheat the bed and nozzle to printing temperature first, then perform the paper test. If your printer has a bed leveling mode, use that — it automates the preheat step.

How often should I re-level my bed?

Check before every print for the first month while you learn how your printer settles. After that, check every few prints or whenever you notice the first layer not sticking evenly. If your bed stays level for weeks at a time, you can check less often — but do not skip it entirely, as even small shifts affect print quality.

What happens if the bed is too high or too low?

If the bed is too high (nozzle too far away), filament will not stick and will ball up on the nozzle. If the bed is too low, the nozzle will scrape the bed surface or jam plastic into it, which can damage both the nozzle and the bed. Either extreme ruins the first layer and wastes filament.